Correlation between the in-vitro and in-vivo Antihyperglycemic Effect of Ocimum Sanctum, Trigonella Foenum Graecum and Curcuma Longa

Abstract

This study is carried out to investigate the correlation between the in-vitro and in-vivo studies which demonstrates the antihyperglycemic effect of Trigonella foenum graecum, Ocimum sanctum and Curcuma longa extracts. Methanolic seed extract of Trigonella foenum graecum, methanolic leaf extract of Ocimum sanctum, ethyl acetate rhizomes extract of Curcumina longa are prepared and supplied by Sami labs, Bangalore, India on request. In-vitro studies such as alpha glucosidase inhibitory and DPP-IV inhibitory activity were done for all the three extracts as per previous studies. After Institutional animal ethical committee clearance male albino rats (155-215 g) were divided into 5 groups. Each group consists of randomly assigned 6 albino rats. The placebo (Normal saline) control group, Standard (Vildagliptin) group and 3 above mentioned extract groups. Oral glucose tolerance test (OGTT) was done. Blood samples were collected for blood sugar estimation at-30 (before extract),0, 15, 45 minutes and blood sugar levels were done by enzymatic assay. Results: The maximum alpha-glucosidase inhibitory activity at 100 μg/ml by Trigonella foenum graecum extract was 68% with IC 50 value of 57.25, Ocimum sanctum leaf extract was 65% with IC 50 value of 59.55, Curcuma longa was 72% with IC 50 value of 56.79 when compared to the Acarbose (STD) of 94% with IC 50 values of 42.78. The maximum % of DPP IV inhibition at 320 μg/ml of Trigonella foenum graecum extract was 77.84% with IC 50 value of 52.26, Ocimum sanctum extract was 86.98% with IC 50 value of 46.08 and Curcuma longa was 76.47% with IC 50 value of 55.06 when compared to the Vildagliptin (STD) was 80.15% with IC 50 value of 22.98. The OGTT results of Ocimum sanctum (200 mg/kg) shows reduction in blood glucose (p=<0.05) at 15 minutes and significant reduction (p=<0.001) at 45 minutes and Trigonella foenum graecum (2 gm/kg) showed significant reduction in blood glucose (p=<0.001) at 15 minutes when compared to control. Further clinical studies are necessary to establish the therapeutic potential of these extracts in the treatment of type 2 diabetes mellitus. Conclusion: Ocimum sanctum leaf extract, Trigonella foenum graecum seed extract shows significant alpha-glucosidase and DPP-IV inhibitory activity which correlates with the antihyperglycemic effects by in-vivo oral glucose tolerance test. Further clinical studies are necessary to establish the therapeutic potential of these extracts in the treatment of type 2 diabetes mellitus.